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how to solve? 1

Old 5th July 2007 | 17:05
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how to solve? 1

airplane desceding a 12% slope while maintaining a GS of 540.

What is the rate of descend aprox?


thanks
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Old 5th July 2007 | 18:17
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From: Blighty
D'oh, very simple, but forgotten how! Isnt it:

G/S(ft per min)*(Glide slope in degrees/60)=Rate of Descent

I keep gettin 6201 ft/min ROD on a 6.8deg slope, which seems unusaully high...
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Old 5th July 2007 | 18:32
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For the required rate of descent multiply the descent angle by the NM/minute times 100.

Taking your example...

540kt = 9NM/min
12° x 900 = 10800'/min.

But... who would fly a 12° angle
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Old 5th July 2007 | 18:38
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Wasnt it a 12% gradient and not 12 degree? a little steep!
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Old 5th July 2007 | 18:45
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Space shuttle?
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Old 5th July 2007 | 19:28
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Capt. Slow

Oh, sorry for that! You are absolutely right - it is gradient, not a slope...

In that case, to find the rate required, multiply the gradient by the GS (or rather TAS).

12% x 540 = 6480'/min.

Regards
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Old 5th July 2007 | 19:32
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So call it an even 6300' Well your method seems a lot simpler than mine, might adopt that for the future...
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